The present invention relates to a chromatograph mass analysis data processing apparatus for processing data collected by a chromatograph mass spectrometer such as a gas chromatograph mass spectrometer (GC/MS) and a liquid chromatograph mass spectrometer (LC/MS).
In chromatograph mass spectrometers such as a GC/MS and LC/MS, data having three dimensions, i.e. a retention time, mass-to-charge ratio, and signal intensity, is collected. The data collected is processed to create a mass chromatogram, mass spectrum, and total ion chromatogram. The mass chromatogram shows the relationship between the retention time and the signal intensity for a specified mass-to-charge ratio, the mass spectrum shows the relationship between the mass-to-charge ratio and the signal intensity for a specified retention time, and the total ion chromatogram shows the relationship between the retention time and the signal intensity without the limitation of mass-to-charge ratio.
Conventional apparatuses of this kind are generally capable of displaying the aforementioned graphs in various forms in order to analyze the result collected as previously described. The apparatus disclosed in Patent Document 1, for example, is capable of displaying a graph in which many lines of chromatograms in different colors are overlapped, or displaying a graph in which many mass chromatograms with base lines slightly shifted along the direction of the longitudinal axis (axis of signal intensity) are overlapped. With this apparatus, it is possible to compare the shapes of plural mass chromatograms with respect to various mass-to-charge ratios and to perform a waveform processing.
One known displaying method for grasping the whole data having the aforementioned three dimensions is creating a graph, as described in Patent Document 2, with a retention time and a mass-to-charge ratio on the mutually orthogonal two axes and with a signal intensity represented with a contour or contours. This graph is hereinafter called “an isointensity line graph.” In Patent Document 2, if any retention time is specified by a cursor displayed on the isointensity line graph, a mass spectrum for the retention time is displayed, and if any mass-to-charge ratio is specified by the cursor, a mass chromatogram for the mass-to-charge ratio is displayed.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2007-147464
Patent Document 2: Japanese Unexamined Patent Application Publication No. 2001-165922